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1.
Bull Entomol Res ; 109(2): 178-190, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29784067

RESUMO

Anastrepha fraterculus (Wiedemann), a pest of great economic importance in South America, needs urgently to be controlled by environmentally friendly methods such as the sterile insect technique for which mass rearing of insects is required. Because oogenesis takes place during the adult stage, mass-rearing facilities should provide the females a diet that maximizes egg production at the lowest cost. Accordingly, we investigated the effect of artificial protein sources in the adult diet (yeast derivatives of different cost but with similar amino acids profiles, and the addition of wheat germ) on fecundity. Additionally, we evaluated different ratios of yeast derivatives or wheat germ on ovary maturation, fecundity, and fertility as well as their association with the nutrient content of females. Females fed hydrolyzed yeast and yeast extract attained the highest fecundity level, and those fed brewer's yeast the lowest. Reducing the amount of hydrolyzed yeast, an expensive protein source, in the diet negatively affected fecundity and ovary maturation. Increasing the amount of brewer's yeast, a low-cost protein source, did not favor fecundity. The addition of wheat germ in the adult diet improved fecundity regardless of the yeast derivate considered. Percentage of egg hatch was not affected by the diet. Nutrient content of A. fraterculus females varied according to the adult diet provided and mating status. Our findings provide novel baseline information to understand the role of nutrition on reproductive performance of A. fraterculus females and are discussed in the context of resource allocation. They also provide valuable advances in the search for cost-effective adult diets at fruit fly mass rearing facilities.


Assuntos
Dieta , Oviparidade , Tephritidae/fisiologia , Animais , Feminino , Fertilidade , Ovário/fisiologia , Triticum , Leveduras
2.
Opt Express ; 26(4): 4621-4630, 2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29475310

RESUMO

In this paper, we report the benefits of working with photonic molecules in macroporous silicon photonic crystals. In particular, we theoretically and experimentally demonstrate that the optical properties of a resonant peak produced by a single photonic atom of 2.6 µm wide can be sequentially improved if a second and a third cavity of the same length are introduced in the structure. As a consequence of that, the base of the peak is reduced from 500 nm to 100 nm, while its amplitude remains constant, increasing its Q-factor from its initial value of 25 up to 175. In addition, the bandgap is enlarged almost twice and the noise within it is mostly eliminated. In this study we also provide a way of reducing the amplitude of one or two peaks, depending whether we are in the two- or three-cavity case, by modifying the length of the involved photonic molecules so that the remainder can be used to measure gas by spectroscopic methods.

3.
J Appl Microbiol ; 125(1): 181-189, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29573518

RESUMO

AIMS: The sigma E (AlgU) in Azotobacter vinelandii has been shown to control the expression of cydR gene, a repressor of genes of the alternative respiratory chain, and alginate has been considered a barrier for oxygen diffusion. Therefore, the aim of the present study was to compare the respiratory activity of an alginate nonproducing strain, lacking the sigma factor E (algU-), and polymer-producing strains (algU+) of A. vinelandii under diazotrophic conditions at different aeration conditions. METHODS AND RESULTS: Our results reveal that under diazotrophic and high aeration conditions, A. vinelandii strain OP (algU-) had a specific oxygen consumption rate higher (30 and 54%) than those observed in the OP algU+-complemented strain, named OPAlgU+, and the ATCC 9046 respectively. However, the specific growth rate and biomass yields (based on oxygen and sucrose) were lower for OP cultivations as compared to the algU+ strains. These differences were partially explained by an increase in 1·5-fold of cydA relative expression in the OP strain, as compared to that obtained in the isogenic OPAlgU+ strain. CONCLUSIONS: Overall, our results confirm the important role of algU gene on the regulation of respiratory metabolism under diazotrophic growth when A. vinelandii is exposed to high aeration. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights the role of AlgU to control respiration of A. vinelandii when exposed to diazotrophy.


Assuntos
Alginatos/metabolismo , Azotobacter vinelandii , Fixação de Nitrogênio/fisiologia , Oxigênio/metabolismo , Azotobacter vinelandii/genética , Azotobacter vinelandii/metabolismo , Azotobacter vinelandii/fisiologia , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo
4.
Bull Entomol Res ; 107(6): 756-767, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28382881

RESUMO

The optimal use of available host by parasitoid insects should be favoured by natural selection. For solitary parasitoids, superparasitism (i.e. the egg-laying of several eggs/host) may represent a detrimental phenomenon both in a biological and an applied sense, but under certain circumstances it may be adaptive. Here, we studied the effects of increasing levels of superparasitism (LSPs, number of parasitoid larvae/host) on fitness-related parameters of the immature and adult stages of Diachasmimorpha longicaudata, a solitary endoparasitoid parasitizing Ceratitis capitata. We investigated the moment when supernumerary parasitoid larvae are eliminated and the effects produced by this process, together with its repercussion on female fecundity, parasitism rate, sex ratio, adult survival, flight ability and body size. Complete elimination of competitors occurred soon after larval hatching, before reaching the second larval stage. Elimination process took longer at higher LSPs, although a normal developmental (egg-adult) time was achieved. For LSPs 1, 2, 3 and 5 the effects on parasitoid emergence were mild, but LSP 10 led to the death of all developing parasitoids. Aside from this, to develop in superparasitized hosts did not significantly affect any of the evaluated parameters, and only a female-biased sex ratio was observed at higher LSPs. However, the effects of superparasitism on the adults may have a different outcome under more variable conditions in the field, once they are released for biological control purposes.


Assuntos
Ceratitis capitata/parasitologia , Interações Hospedeiro-Parasita , Vespas/crescimento & desenvolvimento , Animais , Tamanho Corporal , Feminino , Fertilidade , Voo Animal , Masculino , Razão de Masculinidade
5.
Bull Entomol Res ; 104(3): 376-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24702958

RESUMO

The South American fruit fly, Anastrepha fraterculus, is a complex of cryptic species composed of at least seven morphotypes. Some of them, such as the Peruvian and Brazilian 1 morphotypes (which include Argentinean populations), exhibit strong pre-copulatory isolation, yet it is possible to obtain heterotypic crosses when forcing copulation of adults under laboratory conditions. The cross involving Peruvian males and Argentinean females produces F1 offspring with reduced viability in terms of egg hatch. This low hatchability could be caused by a reduced amount of sperm transferred to and stored by females mated with heterotypic males, which in turn could affect their post-copulatory behaviour. To test these hypotheses, we investigated sperm transfer and female mating and remating behaviour for homotypic and heterotypic crosses between adults of two morphotypes (Brazilian 1 [Argentina] and Peruvian [Peru]) of the A. fraterculus cryptic species complex. As reported before, Argentinean males and females mated earlier in the day than the other three mating combinations. Peruvian females engaged in shorter copulation times than Argentinean females. Peruvian females tended to store smaller quantities of sperm than Argentinean females, and almost a half of the crosses involving Argentinean males and Peruvian females were unsuccessful (no sperm transfer). However, there was no evidence that the cross between Peruvian males and Argentinean females resulted in storage of a critically small amount of sperm (posing risk of sperm shortage). Argentinean females were more willing to remate than Peruvian females, irrespective of male morphotype, but latency to remating was not affected by male or female morphotype. This study shows that mating behaviour differs between some of the A. fraterculus complex morphotypes, with female but not male morphotype determining female likelihood to remate.


Assuntos
Copulação , Tephritidae/fisiologia , Animais , Argentina , Feminino , Hibridização Genética , Masculino , Peru , Reprodução , Especificidade da Espécie , Espermatozoides/fisiologia , Tephritidae/genética
6.
Bull Entomol Res ; 103(3): 310-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23340454

RESUMO

The sterile insect technique (SIT) has been proposed as an area-wide method to control the South American fruit fly, Anastrepha fraterculus (Wiedemann). This technique requires sterilization, a procedure that affects, along with other factors, the ability of males to modulate female sexual receptivity after copulation. Numerous pre-release treatments have been proposed to counteract the detrimental effects of irradiation, rearing and handling and increase SIT effectiveness. These include treating newly emerged males with a juvenile hormone mimic (methoprene) or supplying protein to the male's diet to accelerate sexual maturation prior to release. Here, we examine how male irradiation, methoprene treatment and protein intake affect remating behavior and the amount of sperm stored in inseminated females. In field cage experiments, we found that irradiated laboratory males were equally able to modulate female remating behavior as fertile wild males. However, females mated with 6-day-old, methoprene-treated males remated more and sooner than females mated with naturally matured males, either sterile or wild. Protein intake by males was not sufficient to overcome reduced ability of methoprene-treated males to induce refractory periods in females as lengthy as those induced by wild and naturally matured males. The amount of sperm stored by females was not affected by male irradiation, methoprene treatment or protein intake. This finding revealed that factors in addition to sperm volume intervene in regulating female receptivity after copulation. Implications for SIT are discussed.


Assuntos
Controle de Insetos/métodos , Metoprene/toxicidade , Comportamento Sexual Animal/fisiologia , Tephritidae/fisiologia , Análise de Variância , Animais , Argentina , Proteínas Alimentares/farmacologia , Feminino , Fertilidade/efeitos da radiação , Raios gama , Masculino , Pupa/efeitos da radiação , Comportamento Sexual Animal/efeitos dos fármacos
7.
Bull Entomol Res ; 103(1): 1-13, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22929968

RESUMO

Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competitiveness of sterile laboratory males and females that were treated with methoprene (either the pupal or adult stage) and were kept under different regimes of adult food, which varied in the protein source and the sugar:protein ratio. Experiments were carried out under semi-natural conditions, where laboratory flies competed over copulations with sexually mature wild flies. Sterile, methoprene-treated males that reached sexual maturity earlier (six days old), displayed the same lekking behaviour, attractiveness to females and mating competitiveness as mature wild males. This effect depended on protein intake. Diets containing sugar and hydrolyzed yeast allowed sterile males to compete with wild males (even at a low concentration of protein), while brewer´s yeast failed to do so even at a higher concentration. Sugar only fed males were unable to achieve significant numbers of copulations. Methoprene did not increase the readiness to mate of six-day-old sterile females. Long pre-copulatory periods create an additional cost to the management of fruit fly pests through the sterile insect technique (SIT). Our findings suggest that methoprene treatment will increase SIT effectiveness against A. fraterculus when coupled with a diet fortified with protein. Additionally, methoprene acts as a physiological sexing method, allowing the release of mature males and immature females and hence increasing SIT efficiency.


Assuntos
Proteínas Alimentares , Hormônios Juvenis , Metoprene , Controle Biológico de Vetores/métodos , Comportamento Sexual Animal/efeitos dos fármacos , Tephritidae , Ração Animal , Animais , Suplementos Nutricionais , Feminino , Masculino , Controle Biológico de Vetores/economia , Pupa/crescimento & desenvolvimento , Maturidade Sexual/efeitos dos fármacos , Tephritidae/crescimento & desenvolvimento
8.
Int J Neurosci ; 123(6): 400-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23297730

RESUMO

Information regarding the epidemiology of spasticity in patients with multiple sclerosis (MS) in Spain is limited. This cross-sectional survey-based study was undertaken to evaluate the symptoms, severity and consequences of MS-related spasticity (MSS) and to estimate the prevalence of MSS overall and according to the degree of severity (mild/moderate/severe). Adult MS patients (n = 8463) from the two main Spanish MS patients' associations were asked to complete a web-based questionnaire. Two thousand six hundred twenty seven responses were received, of which 2029 were valid for analysis. Two thirds were for women. The mean age of respondents was 40.2 years and the mean MS duration was 8.7 years. MSS was reported by 65.7% of respondents with 40% of these rating it as moderate/severe. MS patients with spasticity experienced more symptoms (including greater difficulty walking), consumed more healthcare resources (including care and rehabilitation sessions), and had a higher degree of disability than patients without spasticity. There was a significant correlation between increasing severity of spasticity and worsening of symptoms. Only 42.4% of patients with moderate spasticity and 52.6% of patients with severe spasticity were currently receiving antispasticity medication compared with 69% and 79%, respectively, reported in a similar survey-based study from the United States; this is likely to reflect regional variations in practice. Early and effective treatment of MSS is important to minimise the consequences of spasticity-related symptoms on patients' quality of life and the economic burden on healthcare systems. In appropriate patients, antispastic treatment, including pharmacotherapy and physiotherapy/rehabilitation, may provide such benefits.


Assuntos
Esclerose Múltipla/epidemiologia , Espasticidade Muscular/epidemiologia , Adulto , Efeitos Psicossociais da Doença , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico , Espasticidade Muscular/complicações , Espasticidade Muscular/diagnóstico , Prevalência , Índice de Gravidade de Doença , Espanha/epidemiologia
9.
Bull Entomol Res ; 102(4): 435-43, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22360877

RESUMO

As a prerequisite for area-wide application of the sterile insect technique in an area encompassing northern Argentina and southern Brazil, prezygotic and postzygotic reproductive compatibility among three geographically distant populations in the area was tested. In field cages, sexually mature adults of each population were found to be sexually compatible, mating duration was not affected by fly origin and there was no clear evidence of spatial partition of mating location. In the laboratory, homotypic and heterotypic crosses for all possible combinations displayed similar levels of fertility and yielded F1 adults without distortion of the sex ratio. Finally, F1 hybrid and parental adults produced equally viable F2 eggs. Put together, our results and those from earlier studies suggest that a large area, ranging from Buenos Aires to the surroundings of São Paulo, could be managed using a single A. fraterculus mass-reared strain. At the northern margin of this area, two A. fraterculus morphotypes appear to coexist in sympatry. We delineate future research to further delimit the distribution of the aff1 morphotype (Argentina-southern Brazil) and to gain insight into evolutionary patterns producing divergence and radiation of tropical fruit fly species.


Assuntos
Reprodução/fisiologia , Tephritidae/fisiologia , Distribuição Animal , Animais , Argentina , Brasil , Feminino , Masculino , Controle Biológico de Vetores/métodos , Reprodução/genética , Comportamento Sexual Animal , Tephritidae/genética
11.
J Appl Microbiol ; 108(1): 55-61, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19583796

RESUMO

AIMS: A two-stage fermentation strategy, based on batch cultures conducted first under non-oxygen-limited conditions, and later under oxygen-limited conditions, was used to improve alginate production by Azotobacter vinelandii (AT6), a strain impaired in poly-beta-hydroxybutyrate (PHB) production. METHODS AND RESULTS: The use of sucrose as carbon source, as well as a high oxygen concentration (10%), allowed to obtain a maximum biomass concentration of 7.5 g l(-1) in the first stage of cultivation. In the second stage, the cultures were limited by oxygen (oxygen close to 0%) and fed with a sucrose solution at high concentration. Under those conditions, the growth rate decreased considerably and the cells used the carbon source mainly for alginate biosynthesis, obtaining a maximum concentration of 9.5 g l(-1), after 50 h of cultivation. CONCLUSION: Alginate concentration obtained from the AT6 strain was two times higher than that obtained using the wild-type strain (ATCC 9046) and was the highest reported in the literature. However, the mean molecular mass of the alginate produced in the second stage of the process by the mutant AT6 was lower (400 kDa) than the polymer molecular mass obtained from the cultures developed with the parental strain (950 kDa). SIGNIFICANCE AND IMPACT OF THE STUDY: The use of a mutant of A. vinelandii impaired in the PHB production in combination with a two-stage fermentation process could be a feasible strategy for the production of alginate at industrial level.


Assuntos
Azotobacter vinelandii/crescimento & desenvolvimento , Azotobacter vinelandii/metabolismo , Hidroxibutiratos/metabolismo , Mutação , Poliésteres/metabolismo , Alginatos , Azotobacter vinelandii/genética , Fermentação , Ácido Glucurônico/biossíntese , Ácido Glucurônico/genética , Ácidos Hexurônicos , Sacarose/farmacologia , Edulcorantes/farmacologia
12.
Platelets ; 21(8): 658-66, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20958115

RESUMO

Studies in animal models are useful to understand the basic mechanisms involved in hemostasis and the functional differences among species. Ultrastructural observations led us to predict differences in the activation and secretion mechanisms between equine and human platelets. The potential mechanisms involved have been comparatively explored in the present study. Equine and human platelets were activated with thrombin (0.5 U/ml) and collagen (20 µg/ml), for 90 seconds, and samples processed to evaluate: i) ultrastructural changes, by electron microscopy, ii) actin polymerization and cytoskeletal assembly, by polyacrylamide gel electrophoresis, and iii) specific molecules involved in activation and secretion, by western blot. In activated human platelets, centralization of granules, cytoskeletal assembly and fusion of granules with the open canalicular system were observed. In activated equine platelets, granules fused together forming an organelle chain that fused with the surface membrane and released its content directly outside the platelets. Human platelets responded to activation with actin polymerization and the assembly of other contractile proteins to the cytoskeleton. These events were almost undetectable in equine platelets. When exploring the involvement of the synaptosomal-associated protein-23 (SNAP-23), a known regulator of secretory granule/plasma membrane fusion events, it was present in both human and equine platelets. SNAP-23 was shown to be more activated in equine platelets than human platelets in response to activation, especially with collagen. Thus, there are significant differences in the secretion mechanisms between human and equine platelets. While in human platelets, activation and secretion of granules depend on mechanisms of internal contraction and membrane fusion, in equine platelets the fusion mechanisms seem to be predominant.


Assuntos
Plaquetas/metabolismo , Plaquetas/ultraestrutura , Citoesqueleto/metabolismo , Fusão de Membrana/fisiologia , Actinas/metabolismo , Animais , Plaquetas/efeitos dos fármacos , Colágeno/farmacologia , Citoesqueleto/ultraestrutura , Cavalos , Humanos , Ativação Plaquetária/efeitos dos fármacos , Polimerização , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , Trombina/farmacologia
13.
J Vet Intern Med ; 23(6): 1232-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19761478

RESUMO

BACKGROUND: Peritoneal D-Dimer concentration can be determined to assess peritoneal fibrinolysis activity in horses with gastrointestinal disorders. However, blood contamination of peritoneal fluid may occur during collection and could alter peritoneal D-Dimer concentration. HYPOTHESIS/OBJECTIVES: Blood contamination in peritoneal fluid does not affect interpretation of peritoneal D-Dimer concentration in horses with colic. ANIMALS: Thirty-four horses with colic and 4 healthy horses. METHODS: Peritoneal fluid and blood samples were simultaneously collected upon admission. Then, peritoneal fluid was serially contaminated with the horse's own blood; final contaminations corresponded to 1, 5, 10, and 20% of blood in peritoneal fluid. D-Dimer concentration was determined in blood, peritoneal fluid, and contaminated peritoneal fluid samples. Data were analyzed using a longitudinal linear model and a generalized estimating equations analysis to assess the quantitative and qualitative variations of the effect of blood contamination on peritoneal D-Dimer concentration. RESULTS: Peritoneal D-Dimer concentration was only quantitatively affected when peritoneal fluid was contaminated at 20% of blood. However, when using increasing cut-off values of peritoneal D-Dimer concentration (100, 2,000, 8,000, and 16,000 ng/mL), this effect disappeared at the highest cut-off values (8,000 and 16,000 ng/mL). When peritoneal fluid contamination was grouped as "minimally contaminated" (< or =1% of blood) and "highly contaminated" (> or =5% of blood), no significant differences on D-Dimer concentration between both groups at each cut-off value were observed. CONCLUSIONS AND CLINICAL IMPORTANCE: Although quantitative results of peritoneal D-Dimer concentration could be affected by high levels of blood contamination (> or =20%), interpretation of increased peritoneal fibrinolytic activity was not significantly affected.


Assuntos
Líquido Ascítico/química , Cólica/veterinária , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Doenças dos Cavalos/diagnóstico , Animais , Biomarcadores , Sangue , Cólica/diagnóstico , Feminino , Doenças dos Cavalos/sangue , Cavalos , Masculino , Manejo de Espécimes/veterinária
14.
J Vet Intern Med ; 23(4): 882-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19566853

RESUMO

BACKGROUND: Plasma D-dimer concentration is a useful marker to assess systemic coagulation and fibrinolytic activities in humans, dogs, and horses. Peritoneal fibrinolytic activity increases in horses with colic, especially in horses with endotoxin in the peritoneal fluid. HYPOTHESIS/OBJECTIVES: Peritoneal D-dimer concentration can be used to assess peritoneal fibrinolytic activity in horses with severe gastrointestinal (GI) disorders and altered peritoneal fluid. ANIMALS: Two hundred and twenty-one colic horses and 15 control horses. METHODS: Prospective observational clinical study. Blood and peritoneal fluid were collected on admission. Horses were grouped according to diagnosis, peritoneal fluid analysis, and outcome. Peritoneal D-dimer concentration was determined, together with peritoneal tissue-plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) activities. Plasma D-dimer concentration also was measured. RESULTS: Peritoneal D-dimer concentration was significantly higher in all colic groups compared with controls, and in horses with enteritis, peritonitis, and ischemic disorders compared with horses with large intestinal obstructions. Peritoneal D-dimer concentration was significantly higher in horses with altered peritoneal fluid (modified transudate and exudate) compared with horses with normal peritoneal fluid analysis. Plasma D-dimer concentration also was significantly higher in the peritonitis group, and in horses with altered peritoneal fluid analysis. Peritoneal and plasma D-dimer concentrations also were significantly higher in nonsurvivors. Peritoneal d-dimer concentration was significantly correlated with decreased peritoneal t-PA activity and increased peritoneal PAI-1 activity. CONCLUSIONS AND CLINICAL IMPORTANCE: Peritoneal D-dimer concentration is markedly higher in severe GI disorders, and it can be used to assess peritoneal fibrinolytic activity in horses with colic.


Assuntos
Líquido Ascítico/química , Cólica/veterinária , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinólise/fisiologia , Doenças dos Cavalos/metabolismo , Animais , Biomarcadores , Estudos de Casos e Controles , Cólica/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Cavalos , Masculino , Inibidor 1 de Ativador de Plasminogênio , Ativador de Plasminogênio Tecidual
15.
J Vet Intern Med ; 22(1): 238-41, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18289318

RESUMO

BACKGROUND: Template bleeding time (TBT) is considered to be a useful test for detecting platelet function disorders and the effect of platelet-activating drugs, but studies in human medicine have concluded that the test has poor reproducibility and sensitivity. HYPOTHESIS: TBT has poor reproducibility in horses and has insufficient sensitivity to detect the effect of etamsylate on platelet function. ANIMALS: Twenty healthy horses. METHODS: TBT was determined and repeated 2 hours and 30 days later. TBT was also performed 2 hours after IV administration of etamsylate. RESULTS: Although no statistical differences were seen between the TBT values obtained at different times, the coefficients of variation for TBT replicates ranged from 26.8% to 45.5%. The reference range for TBT was 138.4-860.4 seconds. No statistically significant shortening of the mean TBT value was observed after etamsylate administration. CONCLUSION AND CLINICAL IMPORTANCE: TBT has poor reproducibility, and the reference range is too wide to make TBT useful in a clinical setting. Other tests with higher reproducibility should be considered when assessing platelet function disorders in horses.


Assuntos
Tempo de Sangramento/veterinária , Etamsilato/farmacologia , Hemorragia/tratamento farmacológico , Hemostáticos/farmacologia , Análise de Variância , Animais , Tempo de Sangramento/normas , Coleta de Amostras Sanguíneas/métodos , Coleta de Amostras Sanguíneas/veterinária , Etamsilato/uso terapêutico , Hemostáticos/uso terapêutico , Masculino , Contagem de Plaquetas/veterinária , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
J Vet Intern Med ; 22(2): 411-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18312557

RESUMO

BACKGROUND: Septicemia is associated with a systemic inflammatory response, hemostatic activation, and disseminated intravascular coagulopathy (DIC). HYPOTHESIS: Increased plasma d-dimer concentration occurs in septic neonates and can reliably detect sepsis or DIC, and predict death in ill neonatal foals. ANIMALS: 40 septic, 41 nonseptic hospitalized foals, and 22 healthy neonates. METHODS: Prospective observational clinical study. Blood samples were collected on admission, at 24-48 hours after admission, and at the time of discharge or euthanasia. Plasma d-dimer concentration, clotting times, antithrombin activity, and fibrinogen concentration were determined. RESULTS: On admission, d-dimer concentration values were significantly higher in septic foals (median, 25-75th percentiles; 568, 245-2013 ng/mL) compared with the nonseptic and healthy groups (386, 175-559 and 313, 152-495 ng/mL, respectively), and in septic foals at the age of 2-7 days compared with similar-age nonseptic foals. By means of samples taken at 24-48 hours of hospitalization and a cut-off value of > 2000 ng/mL, D dimer concentration was significantly associated with the diagnosis of septicemia (odds ratio [OR] = 19.6, 95% confidence interval [95% CI] 1.9-203) and death (OR = 8.7, 95% CI 1.8-43). Owing to a high false-positive prediction rate (71%), a normal d-dimer concentration is better at eliminating the diagnosis of sepsis than an increased d-dimer concentration at predicting sepsis. Fifty percent of septic foals had a diagnosis of DIC, but d-dimer concentration was not significantly associated with the diagnosis of DIC. CONCLUSIONS AND CLINICAL IMPORTANCE: Septic foals showed a marked activation of coagulation and fibrinolytic systems and a high prevalence of DIC. Increased plasma d-dimer concentration is significantly associated with the diagnosis of sepsis.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Doenças dos Cavalos/sangue , Sepse/veterinária , Distribuição por Idade , Animais , Animais Recém-Nascidos , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/veterinária , Feminino , Cavalos , Modelos Logísticos , Masculino , Razão de Chances , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sepse/sangue
17.
J Vet Intern Med ; 22(6): 1403-10, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18783354

RESUMO

BACKGROUND: Septicemia in human neonates frequently is complicated by activation of the coagulation system, disseminated intravascular coagulation (DIC) and multiple organ failure syndrome, which may contribute to high mortality. In adult horses with DIC, the lung has been the organ most frequently affected by fibrin deposits. In addition, in vivo studies suggest that hemostatic mechanisms may be immature in foals < 1-day old. HYPOTHESIS: Newborn foals with severe septicemia have fibrin deposits in their tissues independently of their age, and these fibrin deposits are associated with organ failure. ANIMALS: Thirty-two septic and 4 nonseptic newborn foals euthanized for poor prognosis. METHODS: Tissue samples (kidney, lung, and liver) collected on postmortem examination were stained with phosphotungstic acid hematoxylin (PTAH) and immunohistochemistry (IHC) for blind histologic examination. A fibrin score (grades 0-4) was established for each tissue sample and for each foal. Medical records were reviewed for assessing clinical evidence of organ failure during hospitalization. RESULTS: Fibrin deposits were found in most septic foals (28/32 when using IHC and 21/32 when using PTAH), independently of the age of the foal. The lung was the most affected tissue (97% of the septic foals). Additionally, organ failure was diagnosed in 18/32 septic foals (8 with respiratory failure, 14 with renal failure), although a statistical association with severe fibrin deposition was not identified. CONCLUSIONS AND CLINICAL IMPORTANCE: Nonsurviving septic foals have fibrin deposits in their tissues, a finding consistent with capillary microthrombosis and DIC.


Assuntos
Animais Recém-Nascidos , Fibrina/metabolismo , Doenças dos Cavalos/patologia , Insuficiência de Múltiplos Órgãos/veterinária , Sepse/veterinária , Animais , Cavalos , Imuno-Histoquímica/veterinária , Rim/patologia , Pulmão/patologia , Insuficiência de Múltiplos Órgãos/metabolismo , Insuficiência de Múltiplos Órgãos/patologia , Sepse/patologia
18.
J Insect Physiol ; 101: 7-14, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28623148

RESUMO

The juvenile hormone (JH) of insects triggers physiological changes related to reproduction in adults of both sexes. Methoprene is a sesquiterpene with some effects that are analogous to those of JH. Treatments with methoprene accelerate sexual maturation in males of the South American fruit fly Anastrepha fraterculus, giving young males a mating advantage over non-treated males of the same age. Here, we evaluated the effects of methoprene treatment on A. fraterculus males after the sexual maturation phase and tested whether this compound provides a long-term mating advantage. Moreover, we took the first step to unravel the mechanisms that underlie male sexual enhancement. We treated males 1day or 8days after adult emergence and compared mate choice between recently matured (young) females and females that had been mature for ca. 10days (aged females). We also addressed methoprene treatment effects on male sexual signalling. We found that methoprene treatment enhanced male sexual competitiveness even after the sexual maturation phase, and the effect did not decrease until males were older than 20days. However, when methoprene treatment was carried out close to sexual maturity, the mating enhancement was no longer observed, suggesting a non-immediate effect and excluding the possibility that methoprene acts as a pheromonal compound. Young and aged females tended to mate more frequently with treated-males. This might indicate that in a context of sexual selection, the potential benefits associated with reproductive success would be similar for females of both ages. Treated males released larger amounts of pheromonal compounds than non-treated males, but their courtship behaviour was not altered to the same extent, suggesting that methoprene treatment may accelerate differently the components of male courtship. We discuss potential benefits of using methoprene to increase the efficiency of the sterile insect technique, which is an environmentally safe method to control this important South American fruit pest.


Assuntos
Hormônios Juvenis/farmacologia , Metoprene/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Maturidade Sexual , Tephritidae/efeitos dos fármacos , Tephritidae/fisiologia , Animais , Feminino , Masculino
19.
Arch Pediatr ; 23(8): 840-4, 2016 Aug.
Artigo em Francês | MEDLINE | ID: mdl-27345554

RESUMO

Medullary thyroid carcinoma (MTC) is a rare cancer during childhood. MTC is sporadic in approximately 80% of cases and hereditary in 20%. When hereditary, it can be associated with other endocrine neoplasias and/or typical nonendocrine diseases, thus configuring the multiple endocrine neoplasia (MEN) syndromes. Children with clinically obvious MTC belong to MEN 2A or 2B families, related to RET mutations. The standard treatment is total thyroidectomy and central neck dissection. However, treatment of advanced MTC has not yet been standardized, even if a new tyrosine kinase inhibitor specific to RET mutation has changed the outcome of such patients. Vandetanib plays a role in the treatment of children with metastatic, locally advanced and nonoperable MTC, with good tolerance. We report the 5-year treatment of an 11-year-old patient, with vandetanib and without thyroid surgery.


Assuntos
Carcinoma Neuroendócrino/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/secundário , Criança , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Neoplasia Endócrina Múltipla Tipo 2b/patologia , Neoplasias da Glândula Tireoide/patologia
20.
Oncogene ; 18(39): 5473-6, 1999 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-10498901

RESUMO

The role of oncogenes in pituitary tumorigenesis remains elusive since few genetic changes have been identified so far in pituitary tumors. Pituitary tumor-transforming gene (pttg) has been recently cloned from rat GH4 pituitary tumor cells. We have previously isolated and characterized hpttg from human thymus. In the present study, we analyse the expression of hpttg mRNA in a series of human pituitary adenomas. We show that hpttg is highly expressed in the majority of pituitary adenomas while only very low levels of mRNA can be detected in normal pituitary gland by Northern blot analysis. hPTTG protein was immunolocalized mainly in the cytoplasm of adenoma cells. Other common extra-cranial malignant tumors were also analysed by immunohistochemistry. Interestingly, strong hPTTG immunoreactivity was detected in most adenocarcinomas of mammary and pulmonary origins.


Assuntos
Proteínas de Neoplasias/biossíntese , Neoplasias Epiteliais e Glandulares/metabolismo , Proteínas Oncogênicas/biossíntese , Neoplasias Hipofisárias/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/metabolismo , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/genética , Neoplasias Epiteliais e Glandulares/genética , Proteínas Oncogênicas/análise , Proteínas Oncogênicas/genética , Hipófise/metabolismo , Neoplasias Hipofisárias/genética , RNA Mensageiro/biossíntese , Securina , Células Tumorais Cultivadas
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